I can't believe what you guys are finding. I haven't looked in a while but dropped off some stuff at GoodWill today and didn't see a single tennis racket in the place.

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The key is fortitude. There are about six places I frequent. I hit them all on a weekly basis, spending about five minutes in each on the way home from work. Although I have "harvested" more finds from some, I have found something nice at all of them, and it is supremely unpredictable as to when something will show up. Sometimes, a particular location will run dry for four months.